Field of the Invention
The invention relates to a method of producing a rotor blade according to the preamble of claim 1, and well as to a rotor blade produced in a method in accordance with the invention according to the preamble of claim 6.
Methods of producing rotor blades are naturally known in the prior art.
As a rule, conventional rotor blades have two half shells, along the longitudinal direction of which one belt is provided in each case. The belt is a fibre-reinforced region of the half shell of the rotor blade which is capable of being loaded relatively heavily mechanically. A single web or a plurality of webs, which increases or increase the buckling resistance and the bending resistance of the rotor blade, is or are provided between the belts of the mutually opposed half shells of a rotor blade. The half shells of the rotor blade are glued to each other at their front and rear edges and are glued to the webs along the belts.
The regions between the front edge and the belt and between the rear edge and the belt of each of the half shells of the rotor blade are conventionally formed in a sandwich design. During the production process a resin system is introduced into a dry, multiple-layer lattice which reacts exothermically in the semi-finished product and hardens under the additional subsequent supply of heat. A fibre-reinforced layer on the outside of the rotor blade and a fibre-reinforced layer on the inside of the rotor blade are provided, between which a foam material is arranged.
Description of the Related Art
A method of producing a fibre-reinforced product using a resin-infusion method RTM (resin transfer moulding) is known from WO 2007/038930 A.
In addition, a method of producing fibre-reinforced plastics material components from dry fibre-containing semi-finished product is known from DE 24 134 09 C1, in which a resin system is introduced into the semi-finished product by means of an injection method. During the hardening of the resin system, the resin system passes through an exothermic peak during an exothermic reaction, which can quite possibly reach 180° C. In addition, after passing through the exothermic peak, for the complete hardening of the resin system the resin system has to be tempered further to a process temperature of from 50° C. to 100° C. over several hours in order to be completely hardened.
In order to produce the rotor blades, therefore, temperature-resistant foam materials are necessary. A drawback of the latter, however, is that they are relatively expensive.
The object of the invention is therefore to make available a method of producing a more inexpensive rotor blade as well as to make available a more inexpensive rotor blade.